Марков, Владимир Александрович, and Александра Сергеевна Фомина. “MULTIVARIATE STATISTICAL METHODS TO IDENTIFY THE ECONOMIC CLUSTERING IN REGIONS ON THE BASIS OF LABOR MARKET INDICATORS”. The Bulletin of the Volga Region Institute of Administration, vol. 37, no. 4, Apr. 2013, pp. 85-92, https://volga-institute.owebs.ru/article/view/23796.